The hours leading up to the NBA trade deadline on Thursday, February 21 will prove quite difficult for Boston Celtics fans. Many will be upset if a major trade involving Kevin Garnett, Paul Pierce or Rajon Rondo gets made. Or, many others will wonder why GM Danny Ainge stood pat. At this point, the former appears more probable than the latter, as a major trade seems to be on the horizon.

But while Pierce will most likely remain in Celtics green, Garnett probably won't play for a team that either convinces him that his best interests lie elsewhere, or blatantly desires his departure. And Rondo would ultimately have no say if Boston decided to part ways with the All-Star point guard.

Since Garnett joined the Celtics in 2007, he has put his heart and soul into the organization. His fire and determination helped Boston to its 17th NBA championship in 2008, and got the squad close to banner 18 in 2010. ﻿﻿﻿Similarly, Rondo's elevation to stardom has paralleled the C's success since Ainge acquired him from the Phoenix Suns on draft day in 2006.

But a lot has happened as the decade has progressed. LeBron James and the Miami Heat have asserted themselves as the class of the Eastern Conference, emphasized by a seven-game series victory over the C's last season that led to their 2012 championship over the Oklahoma City Thunder.

Then, Ray Allen signed with the enemy, inking a deal with Miami. But Garnett re-signed with Boston, instilling Celtics fans with hope that the new “Big Three,” consisting of Pierce, Garnett and Rondo, could repeat a run toward the Finals.

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Will this version of the "Big Three" ever play together again?

This season started off poorly for the Celtics, with lackluster play in the team’s half-court offense, and disparities down low and on the boards. They also suffered from a frequent lack of team chemistry, possibly related to newer acquisitions like Jason Terry, Courtney Lee, Leandro Barbosa and rookies Jared Sullinger and Fab Melo.

In January, Boston fans’ bad dreams turned into a collective nightmare when Rondo went down for the year with a torn ACL, followed by the news of season-ending back surgery for Sullinger (who had contributed big numbers down low during power forward Brandon Bass’ decline). It looked like the end of Boston’s hopes for a Championship run this year, never mind for years to come.

Miraculously, though, the Celtics went on a tear. They beat the defending champion Heat (before even realizing Rondo was out for the year), igniting an 8-2 winning streak. Pierce and Garnett seemed refocused, and the team began pursuing each game with a revitalized spirit and sense of camaraderie.

But even though that run ended last week, it seems all too distant now. Barbosa has since sustained a knee injury of his own, further limiting Boston’s depth. And immediately after the Celtics’ tough win over the Bulls prior to the All-Star break, an obviously exhausted Garnett wore his heart on his sleeve, telling reporters that 2013 would mark his final All-Star Game. He also added “you don’t know what I know,” a cryptic message that might reveal Ainge’s true trade deadline intentions.

Since returning from the break, the Celtics have lost two in a row. Their first loss came at the hands of a Denver Nuggets team that did all it could to try to lose the game, taking poor shots from the field and even airballing free throws.

Their second defeat was delivered by an inconsistent Los Angeles Lakers squad, which never appeared to break a sweat. Kobe Bryant and the Lakers won by 14, while out-rebounding Boston 49-34.

Anyone from Celtics Nation paying attention to the past week realizes that something (or rather, many things) seems to be missing from the dynamic that sparked Boston's seven-game winning streak following Rondo’s injury. Notably, presence under the basket sans-Sullinger has played a big part in the collapse. But team offense on the whole has suffered as well. And exhaustion has clearly set in.

These obstacles will only continue to nag the Celtics going forward. Past Boston teams have survived, and even maintained contention, with dismal rebounding numbers. But they haven’t made runs with struggling half-court offenses and constantly-winded leaders. Pierce and Garnett can only do so much at their respective ages.

That being said, Ainge faces possibly the biggest decision of his career. He can choose to ride this season out. He can sacrifice the present by dealing one of the main anchors of the current Celtics’ generation, Garnett. He can ship Pierce, the captain, the No. 2 scorer and living legend of the Celtics. Or, he can unload one of the most intelligent and instinctively lethal young point guards in Rajon Rondo.

Which Celtic will be traded by the deadline at 3:00 PM?

Kevin GarnettRajon RondoPaul PierceCourtney Lee or Fab MeloJason Terry or Brandon BassNone of the AboveSubmit Votevote to see results

Of course, if Ainge wanted to ship smaller names like guard Courtney Lee and rookie center Fab Melo, the opportunity to expand the point guard or big man spots would exist for Boston. But at this point, the often-unpredictable Ainge might have trouble refraining from a big move, especially given the current set of circumstances (down but not out, and one or two pieces away from contention).

Celtics fans must prepare for the distinct possibility that Garnett or Rondo will be dealt by 3:00 p.m. ET on Thursday. At that point (and depending on the return), Celtics Nation can either start preparing to mourn, or start hyping themselves up for a new-look run at the title.